The optical fiber ribbon is comprised of a plurality of optical fibers, wherein the plurality of optical fibers are placed in parallel in juxtaposition with each other and covered with a ribbon matrix. When the optical fiber ribbon as described above is employed, the separation of a single optical fiber is performed at the end of the optical fiber ribbon, with respect to each optical fiber whereupon the front end of each optical fiber is connected to an optical connector. By means of the optical connector, there takes place input or output of a signal light for each optical fiber.
For example, in optical fiber ribbons disclosed in Japanese Unexamined Utility Model Publication No. S61-185008 and Japanese Unexamined Utility Model Publication No. H4-75304, the periphery of a plurality of optical fibers arranged in parallel to each other is not entirely covered with a ribbon matrix, whereas only a part of the periphery is covered with a ribbon matrix and no rest thereof is covered with the ribbon matrix. Such an arrangement of the optical fiber ribbon as described above enables to facilitate performing the separation of a single optical fiber.
Meanwhile, there may happen to occur some situations that necessitate a separation of a single optical fiber at a midway portion instead of same separation at the end portion of the optical fiber ribbon. In this case, even in case of an optical fiber ribbon having the arrangement disclosed in the above publications, it is necessary to use a special tool for the sake of the separation of a single optical fiber at the midway portion.
However, there are some circumstances, under which there are already kept utilised one or more among the plurality of optical fibers incorporated in the optical fiber ribbon for communication purposes. Under such circumstances, supposing the separation of a single optical fiber is performed at a midway portion, fingers may touch an optical fiber in use, or an optical fiber in use may be sharply bent using a tool, whereby the loss pertaining to the optical fiber in use may temporarily increase. Such increase in the loss may exert any adverse influence upon the communication employing the optical fiber.